Illuminate Surrounded Regions

MATRIX

Problem

Given a 2D binary matrix matrix, transform all '0's that are completely surrounded by '1's into '1's. Any '0's that are on the edge of the matrix or are connected to an edge '0' (directly or through other '0's) should remain as '0's.

Examples

illuminateRegions([
  [1, 1, 1, 1],
  [1, 0, 0, 1],
  [1, 1, 1, 1],
  [1, 1, 1, 1]
])
// returns [
  [1, 1, 1, 1],
  [1, 1, 1, 1],
  [1, 1, 1, 1],
  [1, 1, 1, 1],
] 
// All '0's are surrounded by '1's and are transformed into '1's

illuminateRegions([
  [1, 1, 1, 1, 1],
  [1, 1, 0, 0, 1],
  [1, 1, 1, 0, 1],
  [1, 1, 0, 0, 1],
  [1, 0, 1, 1, 1]
])
// returns [
  [ 1, 1, 1, 1, 1 ],
  [ 1, 1, 1, 1, 1 ],
  [ 1, 1, 1, 1, 1 ],
  [ 1, 1, 1, 1, 1 ],
  [ 1, 0, 1, 1, 1 ]
]
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